Valve-gear for explosive or internal-combustion engines.



No. 741,166. PATENTED OCT, 13, 1903.

P. M. RITES. VALVE GEAR FOR EXPLOSIVE 0R INTERNAL COMBUSTION ENGINES.

APPLIOATION FILED MAY 1. 1902.

.UNiTEQD STATES iatented October 13, 1903 PATENT rricr VALVE-GEAR FOREXPLOSIVE OR INTERNAL-COMBUSTION ENGINES.

SPECIFICATION forming part of Letters Patent No. 741,166, dated October13, 1903.

Application filed May 1, 1902. Serial No. 105,468. (No model.)

T0 on whom, it may concern.-

Be itknown that I, FRANCIS M. RITES, a citizen of the UnitedSt-ates,residing at Ithaca, in the county of Tompkins and State of New York,have invented certain new and useful Improvements in Valve-Gear forExplosive and Internal-Combustion Engines; and I do hereby declare thefollowing to be a full, clear, and exact description of' the invention,such as will enable others skilled in the art to which it appertains tomake and use the same.

My invention relates to improvements in valve-gears for explosive andinternal combustion engines; and it consists in novel means whereby inan engine of either the fourcycle or the two-cycle type the point ofcutoff of explosive mixture may be varied by a single admission -valve.Heretofore automatic cut-off'valvegears for explosive andinternal-combustion engines have usually comprised either a plurality ofvalves in series cont-rolling admission or else a rotary cam movableaxially for varying the point of cutoff for operating anadmission-valve. It is desirable that the number of valves of an engineshall be as small as possible, and it is also desirable when possible toavoid the use of sliding cams, sinceitis difficult to adj ust such camssatisfactorily by an automatic speedgovernor, and particularly by-ashaft-governor. The construction herein illustrated and describedpermits the use of a single admission-valve of the puppet type, whichmay be opened either positively or by suction, but the point of closureof which is determined and may be varied by the valve-gear, ashaftgovernor of simple type being employed to regulate the point ofcut-off when desired.

The objects of my invention are to simplify and improve the valvegear ofexplosive and internalcombustion engines, to permit variation in pointof closure of a single admissionvalve,t-o cause said valve to be openedpositively when necessary, to cause said valve to be closed by directaction of the valve-gear at a variable point in the stroke, asdetermined by the adjustment of the valve-gear, to adapt theimprovements both to four-cycle and to two-cycle engines, and to avoidthe use of a sliding cam for operating the admissionvalve.

I will now proceed to describe my invention with reference to theaccompanying drawings, in which certain valve mechanisms embodyingmyinvention are illustrated, and will then point out the novel featuresin claims.

In the drawings, Figure 1 is a side elevation of an explosive-enginefitted with one form of my improved valve-gear, the admission-valvechamber being shown in section. Fig. 2 is a view similar to Fig. 1, butshows a, somewhat different form of valve-gear. Fig. 3 is a sideelevation and partial section of a vertical two-cycle engine fitted withmy improved valve-gear, hand-operated means being provided forregulating the points of valve-closure.

Referring now to the drawings and at first to Fig. 1 thereof, saidfigure shows an enginecylinder 1, frame 2, fly-Wheel 3, carried on thecrank-shaft, and a governor-weight 4, pivoted to the fly-wheel andcarrying eccentric 5. Upon the crank-shaft is a pinion 6, intermeshingwith a gear 7 and carrying a crank or eccentric pin 8.

Within the admission-valve chamber 9 there is a puppet-valve 10,arranged to be opened by suction due to the forward motion of theengine-piston, the piston not being shown. The valve-stem 11 works insuitable guides. A collar 12 is arranged to slide freely upon it and isoperated by a bell-crank lever 13, connected by a rod 14 to a rocker-arm15, pivoted at 16 to another rocker-arm 17, itself pivoted at 18 to theframe of the engine. Rocker-arm 15 is connected by an eccentricrod 19 tothe eccentric 5. A spring 20 is inclosed between the collar 12 and ahead 21 of the valve-stem 11. Rocker-arm 17 is connected by a rod 22 tothe eccentric or crank pin 8 on gear 7.

A shaft 23, driven by suitable two-to-one gears from the crank-shaft ofthe engine, is provided with a cam 24, operating a lever 25, whichoperates the eXhaust-valve. (Not shown.) Gears '6 and 7 have the samespeed ratio as the gears which drive this shaft 23.

The parts are shown in the positions corresponding to the beginning of asuction-stroke of the engine. The collar 12 has just cleared the spring20, and as the fly-wheel advances said collar will rise still further,permitting the valve 10 to open under the influence of suction in theengine-cylinder produced by the forward motion of the piston; but as theeccentric passes its dead-center the collar 12 begins to move downwardwith respect to the valve-stem 11 and soon engages the spring 20 and bypressing against such spring causes the valve to close. Further movementof the eccentric and of the collar 12 after the seating of the valve 10compresses the spring still further. Also since the crank-pin8 is movingbackward the rocker-arm is carried backward bodily by the rocker-arm 17,so that at the beginning of the next forward stroke of the piston,although there will be somebackward movement of the collar 12, thismovement will not be sufficient to relieve the spring of so much of itstension that the valve 10 can open. Upon the valvestem 11 there may be ashoulder 26, which the sliding collar 12 will engage shortly afterfreeing the spring 20 at the beginning of the ad mission-stroke. Thisinsures positive opening of the admission-valve without interfering inthe least with the closing thereof at a variable point as determined bythe position of the eccentric 5. It is desirable to provide for thispositive openingof the valve,since suction-operated ad mission-valvessometimes stick in theirseats; but when it is not thought necessary toprovide for the positive opening of the admission-valve the rocker-armsl5 and 17 may be omitted and the eccentric 5 may be connected directlyto the bell-crank 13 by an eccentric-rod 27, as shown in Fig. 2. Theadmission-valve gear of this figure may be the same whether the enginebe a two-cycle engine or a four-cycle engine, for the sliding collar 12relieves the spring 20 at or before the beginning of the forward strokeof the piston, andtherefore if the engine be a twocycle engine valve 10will be opened at the beginning of each forward stroke, while if theengine be a four-cycle engine the valve 10 will be opened at thebeginning of the admission-stroke, but will be prevented from opening atthe beginning of the working stroke, first, by the pressure upon it dueto compression, and, secondly, by the pressure upon it dueto ignition ofthe charge in the engine-cylinder. Whether the engine is a two-cycle ora four-cycle engine is determinedby the rate of drive of the shaft 23,operating the exhaustvalve. The gears shown are adapted to drive saidshaft at one-half the speed of the crank-shaft. Hence the engine shownis a four-cycle engine.

The governor operatingthe valve-gear of Fig. 2 may be either of theconstant-lead or of the variable-lead type. The governor shown is of theconstant-lead type, the eccentric being arranged to swing across the-end of the crank-shaft; but for this governor any of the wellknownvariable -lead governors may be substituted. The effect of such agovernor will be to vary the point of closure of the valve 10 byadvancing or retarding relatively to the cycle of the engine the pointat which the collar 12 relieves the spring 20. It

can do no harm if the spring be relieved before the beginning of theadmission-stroke, since the valve cannot open until there is suction inthe engine-cylinder.

Fig. 3 illustrates the application of my invention to a two-cycleengine, and, furthermore, illustrates means for varying the point ofcut-0K by hand. In Figs. 1 and 2 the variation in point of cut-off iseffected automatically by the shaft-governor; but it is frequentlydesirableas, for example,in launeh-. engines-to provide means forvarying the speed by hand. In Fig. 3 the collar-12 upon the stem of thevalve is operated by a lever 28, connected at 29 to the strap 30 of theeccentric 31 and further connected by a link 32 to a pivoted hand-lever33, adapted to be clamped at different positions by means of a sector84: and a suitable clamping device 35. By moving this lever 33 up anddown the points on the valve-stem 11 between which the collar 12vibrates may be varied at will, though the length of the vibrations ofsuch collar remains substantially the same, and thereby the period ofthe stroke at which such collar 12 will encounter the spring 20 andclose the valve 10 may be varied. In order that the reaction of thevalve-gear on the governor may be balanced, a spring 36 is provided,which the shoulder 12 compresses after releasing the spring 20.

In this specification the term two-cycle engine is employed to denoteengines in which in the regular operation of the engine combustionoccurs in the combustion chainber'or cylinder (or in each combustionchamber, if the engine has more than one) once during each double strokeof the piston, and the term four-cycle engine is employed to denoteengines in which in regular operation two or more double strokes of thepiston intervene between successive combustion periods. The termfour-cycle engine thereforeincludes those engines in which three or moredoublepiston-strokes intervene between each combustion period, (what aresometimes termed six-cycle engines being an example,) since the cycle ofsuch engines is, in fact, a mere modification of that of engines inwhich combustion occurs in alternate piston-strokes.

It is obvious that the invention herein illustratedand described issusceptible of many modifications and variations, and I do not limitmyselfto the particular details of construction and arrangement hereinshown and described.

While the valves shown in the drawings are all of the puppet type, itwill be obvious that valves of other types may be used without departingfrom my invention. Puppetvalves are illustrated, because that type ofvalve is usually considered to be preferable to valves of other typesfor use in gas and engine, the combination with an engine cylinder andpiston, and a valve for said cylinder, of valve mechanism for operatingsaid valve comprising ashittin g eccentric variable in throw, avibrating valve-operating member in driving connection therewith, andelastic pressure means interposed between said valve-operating memberand valve, arranged to compensate for variation in the range ofvibration of said member.

2. In an explosive or internal-combustion engine, the combination withan engine cylinder and piston, and a puppet-valve for said cylinder, ofvalve mechanism for operating said valve comprising a shifting eccentricvariable in throw, a vibrating valve-operating member in drivingconnection therewith, and elastic pressure means interposed between saidvalve operating member and valve, arranged to transmit to the valvemotion of the valve-operating member tending to move the Valve towardits seat, and to compensate for variation in the range of vibration ofsaid member.

3. In an explosive or internal-combustion engine, the combination withan engine cylinder and piston, and a valve for said cylinder, of valvemechanism for operating said valve comprising a shifting eccentricvariable in throw, and movable in a path which passes to one side of itscenter of rotation, a vibrating valve-operating member in drivingconnection therewith, and elastic pressure means interposed between saidvalve-operating member and valve, arranged to compensate for variationin the range of vibration of said member.

4. In an explosive or internal-combustion engine, the combination withan engine cylinder and piston, and a puppet-valve for said cylinder, ofvalve mechanism for operating said valve comprising a shifting eccentricvariable in throw, and movable in a path which passes to one side of itscenter of retation,a vibrating valve-operating member in drivingconnection therewith,andelasticpressure means interposed between saidvalveoperating member and valve, arranged to transmit to the valvemotion of the valveoperating member tending to move the valve toward itsseat, and to compensate for variation in the range of vibration of saidmember.

5. In an explosive or internal-combustion engine of the four-cycle type,the combination with an engine cylinder and piston, and a valve for saidcylinder controlling admission and cut-off, of valve mechanism foroperating said valve comprising a continuouslydriven valve-operatingmember which operates with each double stroke of the piston, and elasticpressure means directly interposed between said valve-operating memberand the valve.

6. In an explosive or internal-combustion engine of the four-cycle type,the combination with an engine cylinder and piston, and a valve for saidcylinder controlling admission and'cut-otf, of valve mechanism foroperating said valve comprising a continuouslydriven valve-operatingmember which operates with each double stroke of the piston, and elasticpressure means tending, when operated, to close said valve, directlyinterposed between said continuously-driven valve-operating member andsaid valve.

7. In an explosive or internal-combustion engine of the four-cycle type,the combination with an engine cylinder and piston, and a valve for saidcylinder controlling admission and cut-off, of valve mechanism foroperating said valve comprising a continuouslydriven valve-operatingmember which operates with each double stroke of the piston, means fordriving the same adjustable for varying the point of cut-off, andelastic pressure means interposed between said valve operating memberand the valve.

8. In an explosive or internal-combustion engine of the four-cycle type,the combination with an engine cylinder and piston, and a valve for saidcylinder controlling admission and cut-off, of valve mechanism foroperating said valve comprising a continuously-driven valve-operatingmember, a shifting eccentric which rotates with each double stroke ofthe piston for driving the said member, and elastic pressure meansinterposed between said valve-operating member and the valve.

9. In an explosive or internal-combustion engine of the four-cycle type,the combination with an engine cylinder and piston, and a valve for saidcylinder controlling admission and cut-off, of valve mechanism foroperating said valve comprising a continuouslydriven valve-operatingmember, a shifting eccentric for driving the same, which rotates witheach double stroke of the piston, and a valve-closing spring interposedbetween said valve-operating member and the valve.

10. In an explosive or internal-combustion engine of the tour-cycletype, the combination with an engine cylinder and piston, and apuppet-valve for said cylinder controlling admis sion and cut-off, ofvalve mechanism for operating said valve comprising a continuouslydrivenvalve-operating member which operates with each double stroke of thepiston, and elastic pressure means directly interposed between saidvalve-operating member and the Valve.

11. In an explosive or internal-combustion engine of the four-cycletype, the combination with an engine cylinder and piston, and apuppet-valve for said cylinder controlling admission and cut-oft, ofvalve mechanism for operating saidvalve comprising a continuouslydrivenvalve-operating member which operates with each donble stroke of thepiston, means for driving the same adjustable for varying the point ofcut-oft, and elastic pressure means interposed between saidvalveoperating member and the valve.

12. In an explosive or internal-combustion engine of the four-cycletype, the combination with an engine cylinder and piston, andapuppet-valve for said cylinder controlling admission and cut-off, ofvalve mechanism for operating said valve com prising acontinuouslydriven valveoperating member, a shifting eccentric fordriving the same which rotates with each double stroke of the piston,and elastic pressure means interposed between said valve-operatingmember and the valve.

13. In an explosive or internal-combustion engine of the four-cycletype, the combination with an engine cylinder and piston, and apuppet-valve for said cylinder controlling ad mission and cut-oil, ofvalve mechanism for operating said valve comprising acontinuouslydrive'n valve-operating member, a shifting eccentric fordriving the same which rotates with each double stroke of the piston,and a valve-closing spring interposed between said valve-operatingmember and the valve.

14:. In an explosive or internal-combustion engine, the combination withan engine cylinder and piston, and a valve for said cylinder controllingadmission and cut-off, of a reciprocating valve-operating member,ashifting eccentric variable in throw, rotating with each double strokeof the piston,an eccentricrod therefor connected to said reciprocatingmember, and a closing-spring interposed between said reciprocatingmember and the valve, which is relieved by said member prior to theopening of the valve.

15. In an explosive or internal-combustion engine, the combination withan engine cylinder and piston, and a puppet-valve for said cylindercontrolling ad mission and cut-off, of a reciprocating valve-operatingmember, a shifting eccentric variable in throw, rotating with eachdouble stroke of the piston, an eccentric-rod therefor connected to saidreciprocating member, and a closing-spring interposed between saidreciprocating member and the valve, which is relieved by said memberprior to the opening of the valve.

16. In an explosive or internal-combustion engine of the four-cycletype,the combination with an engine cylinder and piston, and a valve forsaid cylinder controlling admission and cut-ofi, of a reciprocatingvalve -operating member, a shifting eccentric variable in throw,rotating with each double stroke of the piston, an eccentric-rodtherefor connected to said reciprocating member, and a closing-springinterposed between said reciprocating member and the valve, which isrelieved by said member prior to the opening of the valve.

17. In an explosive or internal-combustion engine of the four-cycletype,the combination with an engine cylinder and piston, and apuppet-valve for said cylinder controlling admission and cut-off, of areciprocating valve-operating member, an eccentric rotating with eachdouble stroke of the piston, an eccentricrod therefor connected to saidreciprocating member, and a closing-spring interposed between saidreciprocating member and the valve, which is relieved by said memberprior to the opening of the valve.

18. In an explosive or internal-combustion engine of the four-cycletype,the combination with an engine cylinder and piston, and a valve forsaid cylinder controlling admission and cut-off, of valve mechanism foroperating said valve comprising a valve-actuating device, areciprocating member for operating the same arranged to reciprocate witheach double stroke of the piston,and elastic pressure means interposedbetween said actuating device and the valve.

19. In an explosive or internal-combustion engine of the four-cycletype,the combination with an engine cylinder and piston,and apuppet-valve for said cylinder controlling admission and cut-off, ofvalve mechanism for operating said valve comprising a valve-actuatingdevice, a reciprocating member for operating the same arranged toreciprocate with each double stroke of the piston, and elastic pressuremeans interposed between said actuating device and the valve.

20. In an explosive or internal-combustion engine, the combination withan engine cylinder and piston, and a puppet-valve for said cylindercontrolling admission and cut-off, of valve mechanism for operating saidvalve comprising a reciprocating valve-actuating device located inproximity to the stem of said valve, a shifting eccentric of variablethrow, an eccentric-rod connecting said eccentric to said reciprocatingmember, and a spring surrounding the stem of said valve and engaging thesame and the said reciprocating member, arranged to transmit to thevalve motion of the said reciprocating member tending to move the valvetoward its seat, and to compensate for variation in the range ofvibration of said member.

21. In an explosive or internal-combustion engine, the combination withan engine cylinder and piston, and a valve for said cylinder controllingadmission and cut-01f, of valve mechanism for operating said valvecomprising a reciprocating valve-actuating device, means comprising anautomatic speed-governor for operating the same, a spring inter posedbetween said reciprocating valve-actuating device and the valve, and asecond spring counteracting the reaction of said first spring on thegovernor.

22. In an explosive or internal-combustion engine, the combination withan engine cylinder and piston, and a valve for said cylinder controllingadmission and cut-off, of valve mechanism for operating said valvecomprising a reciprocating valve-actuating device, means comprising anautomatic shifting-eccentric governor for operating the same, a springinterposed between said reciprocating valve-actuating device and thevalve, and a second spring counteracting the reaction of said firstspring on the governor.

23. In an explosive or internal-combustion engine, the combination witha valve, of two actuating devices driven at different speeds, areciprocating member driven by the slower moving of said actuatingdevices, another reciprocating member mounted on said first member anddriven by the other of said actuating devices, and means forcommunicating motion from said second reciprocating member to saidvalve.

24. In an explosive or internal-combustion engine, the combination witha valve, of two actuating devices driven at difierent speeds, the fastermoving of said actuating devices being a shifting eccentric adjustableduring the operation of the engine, a reciprocating member driven by theslower moving of said actuating devices, another reciprocating membermounted on said first member and driven by' said shifting eccentric, andmeans for communicating motion from said second reciprocating member tosaid valve.

25. In an explosive or internal-combustion engine, the combination withtwo actuating devices driven at dilferent speeds, and two reciprocatingmembers each driven by one of said actuating devices, the faster movingof said-members being mounted upon the slowermoving member, and meansoperated by said faster-moving member regulating admission of fuel tothe engine-cylinder.

26. In an explosive or internal-combustion engine, the combination oftwo actuating devices driven at diiferent speeds, a reciprocating memberdriven by the faster of said actuating devices, a support for saidreciprocating member, to which the latter is fulcrumed, said supportmovably mounted and reciprocated by the slower moving of said actuatingdevices, and operated by said reciprocating member regulating theadmission of fuel to the engine.

In testimony whereof I affix my signature in the presence of twowitnesses.

FRANCIS M. RITES.

Witnesses: I

JARED T. NEWMAN, Z. I-I. STONE.

